Spectra from faint, distant Galaxies

The spectra (brightness as a function of wavelength) for ten of the confirmed galaxies in the very distant, young cluster found near the radio galaxy TN J1338-1942 . Each galaxy displays a sharp peak in colour showing the signature of its hydrogen gas - this is the redshifted Lyman-alpha emission line.

The galaxy spectra shown were obtained by FORS2 in the MXU-mode on May 20, 21 and 22, 2001. Exposures of 31500 seconds and 35100 seconds, respectively, were made through two masks under photometric conditions, with seeing 1.0 arcsec and slit sizes of 1 arcsec. The 600RI grism was used; it has peak efficiency 87%, resolution R = 1011 at 663.0 nm and spectral dispersion of 0.132 nm/pixel, corresponding to 290 km/s at z = 4.1.



About the Image

Release date:9 April 2002
Related releases:eso0212
Size:999 x 680 px

About the Object

Name:TN J1338-1942
Type:• Early Universe : Galaxy : Activity : AGN
• X - Galaxies
• X - Quasars & Black Holes
Distance:z=4.11 (redshift)

Image Formats

Fullsize Original
272.8 KB
Large JPEG
159.0 KB
Screensize JPEG
154.4 KB

Colours & filters

Very Large Telescope


Also see our